The present invention relates to a vehicle having an arrangement of means enabling firefighters to fill a traction battery of said vehicle, notably with an extinguishing fluid such as water. It is notably, but not exclusively, applicable to lithium-ion (Li-ion) batteries supplying the powertrains of electric or hybrid vehicles.
Because of their high voltage and high energy density, Li-ion batteries are particularly suitable for supplying the powertrain of an electric or hybrid vehicle. In a battery of this type, an Li-ion cell is an elementary component containing a certain quantity of electrolyte, which may be a solid or liquid electrolyte, through which lithium ions can migrate between a cathode and an anode, in order to store or deliver electrical energy. A plurality of Li-ion cells are initially assembled and connected in series and/or in parallel to form a module, after which a plurality of modules are assembled and connected in series and/or in parallel to form a pack.
In view of the many safety devices used by the applicant to prevent and forestall voltage overloads at the terminals of electrochemical cells, it is extremely unlikely that the contents of a pack will catch fire spontaneously. However, if a fire occurs in the vehicle as a whole, regardless of whether this fire is due to a traffic accident or caused by an act of vandalism, the very high evolution of heat in the proximity of the pack may trigger a phenomenon of thermal runaway inside the electrochemical cells. The cells may then, in turn, catch fire within the pack, as soon as they exceed a temperature threshold. Since this is a fire of chemical origin, it is very difficult to extinguish, especially as it is confined within the enclosure formed by the pack.
Indeed, the packs used at the present time are virtually hermetically sealed, notably if they are fitted with a cooling circuit for the circulation of a heat transfer fluid in the pack. This is the case, for example, with packs placed inside the vehicle in a poorly ventilated compartment. Only the inlets and outlets of the cooling circuit allow access to the inside of the pack via small openings, access to which is difficult or even uncertain, especially after a vehicle fire.
Other packs, notably those placed in vehicles with particularly well-ventilated battery locations, for example those placed flat on the outside under the body of the vehicle as in a Kangoo ZE vehicle (trademark registered by the applicant), have no cooling circuit, but are provided with valves to prevent overpressure within the pack. In this case also, the openings left by the valves after a fire in the vehicle are small, and access to them is difficult, or even impossible, in certain architectures.